It is well known that environmental as well as sound conservation necessities dictate the salvage and reprocessing of rubber vehicular tires into scrap for diverse useful purposes as rubber reclamation, fillers, and the like, thereby avoiding unsightly, burdensome and hazardous waste piles of worn tires. Such is primarily effected by chopping and comminution of the rubber tires into smaller pieces and particles. Vehicle tires of all types commonly include steel banding or woven wires of significant cross-sectional diameter in the rim beads which conventionally must be cut or chopped along with the rubber in the comminution and reclamation process. The same is true of any steel belting in the tire sidewalls and tread, but wherein such steel tread or sidewall plies are substantially thinner and web-like as contrasted to the cable-like steel rim beads.
The steel ply sidewall and tread scrap can be generally readily cut by heavy-duty comminuting equipment in chopping the tire, and such steel scrap can be readily separated from the shredded rubber by magnetic or other separation techniques, as is well known in the art.
While passenger vehicle tire beads wires are not of excessively large diameter and can be chopped in the reclaiming process, nonetheless the same contribute to quick wear and dulling of the cutters. The bead cutting problem, however, is far more pronounced with heavy duty and more massive tires, as are used on large trucks, earthmovers, and many other vehicles in heavy load service.
In such tires, the steel wire reinforcement in the annular beads on the outside and inside of the tires is of such size, hardness, and cable-like grouping that the cutting elements of the tire chopping and shredding equipment are quickly and severely damaged in processing such heavy duty tires, with resultant more frequent downtime and expense of equipment for cutter replacement or refurbishment.
This problem has been recognized in the art as shown by Burch U.S. Pat. No. 4,873,759 or Uemura U.S. Pat. No. 3,838,492, for example. In these patents, prior to comminution of the large tires, the steel beads are physically pulled from the tire by a mandrel or rod through a relatively large extruding aperture, the ripped beads thereafter being separately processed by suitable equipment. Accordingly, the tires, after being freed from the damage-causing beads may be comminuted or otherwise processed, and the beads separately processed to reclaim the metal.
It has been found, however, that despite bead puller or ripper equipment of the type illustrated by the Burch and Uemura patents, that the beads cannot be reasonably cleanly torn from the tires, whether passenger or heavy duty, but may jam and/or overload the pulling and tearing equipment. Further, in removing the metal beads, it is desired that only a minimum of rubber or other carcass material be pulled from the tire along with the bead, but with present designs in order to have an aperture of sufficient size for a bead-pulling rod, excess rubber is also pulled through the aperture, and indeed even an overly substantial portion of the carcass, thereby obviating the desired result of removing the bead from the tire with minimum carcass.